Alrighty! Servicing time.
The vehicle has quite a solid history in the book up until 2019 where the service history just vanished. Looking at the last service mileage, the balance on the trip computer I realized it didn’t exist because despite 3 years it was not due.
When I viewed the vehicle I noted it had new belts on it but a bit of a thumping reverb at idle – But I assumed it was exhaust related and since the car was good and drove good and smooth I figured it would be something minor.
It also smoked white, a lot. Quite happy there was no way the turbo was the issue and advised it would be the PCV I trusted the gods of E46 (hi Walt) and bought it regardless.
So lets start at the reason it stood at We Buys Cars and nobody wanted it – Full blown turbo white smoking. This turned out to be the PCV system. This system had been revised from a foam / cotton filter (which was a serviceable item) to a vortex chamber design.
Here you can see the old filter (which I actually soaked and washed the day I got the car as it was rock hard) and the new PCV insert in the background, super easy and quick to swap out and cost very little.
The next issue was the reverb at idle which turned out to be a poked Serpentine Belt Tensioner. Not an expensive part but certainly a part designed and implemented by an Engineer who hated mechanics. To access the tensioner the power steering pump must be removed and moved aside, the starter removed and then the pulley arm loosened from behind the tensioner. From there the pulley comes out the front of the timing cover and you can access the two bolts that hold on the tensioner.
Not wanting to repeat this exercise I bought the pulley wheel / arm and tensioner.
Circled is the tensioner in the bowels of the engine bay:
New wheel / arm:
I went ahead and replaced the Idler Pulley as well – I am thankful I did, it was in an absolute state:
Fresh set of pulleys on fresh belts, much better!
Next up was the pollen filter which was in a righteous state:
And then the Air Filter which was not terrible, the white padding section gets a lot of soot on it, my X1 did the same to its filter:
One of the other issues was that the car refused to get to temp unless you particularly laboured it up a hill or sat in traffic for very long. BMW Thermostats are designed to fail open…. Well that’s not what happened here.
Please keep in mind, everything removed off the car up until this point has all been OEM parts. OEM Tensioners, Wheels, thermostat, PCV etc. So these parts are 18 years old with ease.
On the thermostat housing there are two tabs that hold the thermostat in the housing – these tabs had completely broken off. This left the thermostat to just float around in the housing doing nothing. The tabs were not found so we assume they in the radiator?
Old broken housing:
New housing with new thermostat:
We then went ahead with an oil change and filter change:
I went with 5.5L of Liqui Moly 10W40 Molygen. I went with this for a few reasons – One because Liqui Moly is a German brand and anyone that knows me knows I played a fundamental role in setting up Liqui Moly in the Western Cape so it’s a brand I know inside out. I also went with this oil because I had no prior knowledge of what lubricants had been used in the motor. The motor presented as spotless through the oil cap – No staining or sludge or signs of carbon buildup which is astonishing. I felt a Fully Synthetic (which generally has the ability to clean motors out) would be a risk if there was hidden build up and carbon on valve guides and rings etc.
The 10W40 molygen is a hydrocracked semi synthetic oil and I intentionally went with a 10w as the older diesels are known to smoke a bit of white on startup and my OCD cannot take that. I went with a w40 for the shear stability and to quieten the motor down a bit. Its not as effective as a w30 in terms of fuel economy but I am not chasing 2-3% efficiency here.
I was planning on just going with BMW’s OEM (produced by Shell) Twin Power 5W30 but the Molygen was on special and I was curious about the Molygen concept. Firstly, its lumo green, its like pouring the by product of something from eskom into the engine, it caught me by surprise, it looks awesome.
To explain the green and my curiosity – “The green colour is related to the special wear protection technology of Molygen motor oils. Special “friction modifiers” are used. These are chemical ingredients that smooth the metal surfaces in the motor and even out microscopically small bumps.”
All of this sounds like the good old TWS 10W60 with its high zinc content and special additive package and what better could you want for an 18-year-old diesel with a fragile turbo system. So far, cold starts are seeing nearly instant circulation with minimal clatter and no smoke, at all.
Another issue on the M47N is the EGR Valve, so off this came:
This was miff and caked up to shit. Out with the oven cleaner and yeah, I may have underestimated the sheer amount of crap inside that little valve, I was filthy after!
We tested the valve with a vacuum pump and it is still working beautifully.
Moving forward, brake fluid – BMW has for ages now run a 2 year brake flush service requirement which once out of plan is mostly ignored. The reason you should be changing your brake fluid every 2 years is because Brake Fluid is hydroscopic meaning it regains moisture and when this occurs under heavy use the moisture in the fluid reduces the boiling point of the brake fluid causing a spongey pedal and eventually, complete brake fade and brake pressure loss.
The other reason you change it is because brake fluid lubricates the rubbers and seals in the braking system. Thankfully, unlike coolant brake fluid has an international standard but since BMW brake fluid was on the shelf and it happened to be the cheapest, we got BMW brake fluid and did a full bleed and flush.
As you can see, the fluid was nasty, probably not changed since the last service at BMW in 2008:
Angry German Brake Fluid.
In closing, we did a full coolant drain and fill with fresh coolant and de-ionised water with a quick bleed to check the thermostat was functioning.
We also used a new sump plug and washer.
I still have to do the diesel filter but that will be done by BMW when they complete the recall on my Drivers Side Airbag, the passenger side is already done.
The vehicle has been transformed – Really, it was pretty good off the bat but this has been money so well spent to get it 100% up to date. I am beyond satisfied with the car and it has been absolutely perfect in every way, it drives like a 3 year old BMW.
Goodies still to do!
Mount Wheels & Tyres (they are done and in the car now)
Refit Window Trim and Kidneys (in Gloss black)
Paint and fit thin boot spoiler (ordered)
Drivers Side Airbag Recall
Diesel Filter (Must just be fitted)
Buy 2x New keys and cut and code them
New Nose Roundal (must just fit it)
Leather 6 Speed Gearknob
Tail Gate Shocks
I also fitted a set of Hella wipers to it today – I wanted Bosch Aero’s but they were not in stock and the wipers were driving me mad.
Next post will be the wheels fitted which I was hoping to do tomorrow but I will have to deal with a wheel bearing on a Hyundai i10 instead….. Shoot me.
Thanks for reading!
